Road surfacing machine



Sept. 10, 1935. L, MYERS 2,014,186

ROAD SURFACING MACHINE Filed Jan. 10, 1934 8 Sheets-Sheet l Sept. 10,1935. MYERS 2,014,186

ROAD SURFAC ING MACHINE Filed Jan. 10, 1934 8 Sheets-Sheet 2 H 3 IInventor & .l

Sept. 10, 1935. H, 1.. MYERS ROAD SURFACING MACHINE 8 Sheets-Sheet 3Filed Jan. 10, 1954 Sept. 10,- 1935. H L ER 2,014,186

ROAD SURFAC ING MACHINE Filed Jan. 10, 1934 s Sheets-Sheet 4 flllomcySept. 10, 1935. H. L. MYERS 2,014,186

ROAD SURFACING MACHINE Filed Jan. 10, 1934 8 Sheets-Sheet 5 flllornegInvenlor 8 Sheets-Sheet 6 H. 1.. MYERS ROAD SURFACING MACHINE Filed Jan.10, 1934 Sept. 10', 1935.

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Sept. 10, 1935. H. L. MYERS ROAD SURFACING MACHINE Filed Jan. 10, 1954 8Sheets-Sheet Inventor ,flllomcy y NW km .N\

Sept. 10, 1935. H L, MY'Eg 2,014,186

ROAD SURFACING MACHINE Filed Jan. 10, 1934 8 Sheets-Sheet 8 PatentedSept. 10, 1935 UNETED STATES ROAD SUB/FACING: MACHINE Harry L. Myers,Toledo, Ohio, assignor to The American Floor Surfacing Machine Company,

Toledo, Ohio Application January 10, 1934, Serial No. 706,133

26 Claims. (01. 262-19) This invention relates to the broad class ofgrinding and abrading machines and has more particular reference to aform and style of machine which is especially adapted for road surfacingwork for both newly laid and used highways having concrete andbituminous surfaces.

Those familiar with concrete road construction and highway work areaware of the problems met in the surfacing and maintenance phase of thisline of endeavor. Under practically all conditions, roads are carefullyinspected by State inspectors who subscribe to and permit a tolerance ofunevenness of approximately one-quarter of an inch. The finished roadsurface must come with- H in this tolerance or it becomes necessary forthe contractor to grind off the uneven and high spots before approval isgiven.

These same requirements must be frequently overcome in road patching andreconditioning work. Therefore, certain types of surfacing machines havebeen expressly designed and used to accomplish these tasks. At thepresent time, the two or three different types now endorsed by the tradeare principally designed with the thought in mind of providing forsurfacing work while the construction material or concrete is stillgreen. Hence these machines are generally not practicable orsatisfactory for resurfacing and leveling old roads requiring patchingor other repair work.

The aforesaid types of machines now marketed for this special line ofduty are of a portable, motor-equipped type and embody a wheel-supportedtruck including a tiltable frame having a steering handle at the outeror forward end, a grinding head, and an operating connection between thesource of power or motor and said head. The grinding head is similar tothe horizontally disposed disk abrading head used in floor work and is,therefore, rotatable about a substantially vertical axis, that is, atright angles to the surface being acted on.

Being conversant with these types of machines and their limited degreeof dependable performance, I discovered the need for the development andadoption of a new styled machine characterized by certain structuralrefinements'and features susceptible of permitting it to obtain thedesired result in a more satisfactory and practicable manner.

In reducing the improved machine to practice, I have evolved andproduced a structural assembly of unequaled excellence in that it isespecially useful in levelling humps and irregularities on both old andnew concrete surfaces, is practical for maintenance and repair work,capable of grinding down uneven and high expansion joints, capable ofconditioning cavities for reception of concrete patches, and possessesthe ability to operate and work across joints and edges Without spallingand unnecessarily fracturing ragged edges.

One object of the invention, as will be hereinafter appreciated, is toprovide a machine which is expressly designed to fulfill therequirements under consideration and to accomplish this through theinstrumentality of a simple twowheeled low-built truck attached to thecenter of gravity of a horizontally elongated low-slung chassis frameand to provide a special built drumtype grinding tool at the working endof the frame wherein said tool is rotatable on a horizontal axis atright angles to the truck so that it may be brought into grinding aswell as rolling contact with the surface, thus making it possible toshift the tool in a lateral sweeping manner with respect to the truckand to also adjust it in unison with the movements of the truck toregulate the grinding action in a progressive manner.

Another object is to provide a machine of the aforementioned typewherein the vertical and lateral movements of the tool on acounterbalanced frame and truck arrangement are such as to effectivelyrespond to the natural impulse of the attendant due to the particulardrumtype construction of the grinding head and the fact that by rotatingit on a horizontal axis it literally rolls the working end of the framein a limited arcuate and sweeping path, this being compensated for bythe simple two-wheeled lowbuilt truck support.

A further feature of the invention is predicated on an assemblage of theforegoing type wherein a steering handle is utilized, said handleembodying an upwardly and forwardly inclined reach rod or shaft attachedto the frame inwardly of the tool and having its opposite upper endprovided with hand grips located sufficiently in advance of the tool topermit the operator to work at a safe distance from the tool and, at thesame time, to have positive control of the tool to swing it from side toside in an arcuate path and to produce the requisite downward physicalthrust pressure necessary to regulate both coarse and fine grinding andpulverizing work.

A further object of the invention is to provide a truck-supportedcounterbalanced frame arrangement with the prime'mover on one end andthe tool on the opposite end wherein said parts have the proper ratio inweight to provide sensitive balancing of the frame, and to furtherincorporate in such arrangement a dustcollecting system associated withthe grinding tool and operated by the prime mover so as to carry off thedust and exhaust it toward the rear of the machine so that the workingarea will be clear to the attendant at all times.

More specifically and structurally stated, I aim to provide an expresslydesigned road surfacing machine particularly adapted for the purposesintended in that it includes an appropriate mobile support properlymovable during transportation and while working on the surface beingtreated, there being a suitable frame on this support and said supportbeing so constructed as to include means whereby the frame may be rockedon its transverse axis substantially parallel to the surface and at thesame time swung on its substantially vertical or upright axis, and meansbeing provided for rotatably mounting a cylindrical head on the frame sothat the axis of the head extends in a direction substantially at rightangles to said transverse axis and in a plane substantially parallel tosaid surface so that the grinding means on the periphery of the head mayadequately and aptly engage the surface being worked, the arrangementbeing such that the operator may swing the frame on the aforementionedupright axis in such a way as to cause the head to move from side toside in an arc concentric to said upright axis.

The explicit details of construction and their relative mechanicalco-ordination relied upon to render the machine aptly fitted for thepurposes intended will become more readily apparent from the followingdescription and drawings.

In the accompanying drawings wherein like numerals are employed todesignate like parts throughout the views:

Figure 1 is a side elevational View of one embodiment of the roadsurfacing machine which is hereinafter referred to as a duplex grinder.

Figure 2 is a top plan view of the assembly illustrated in Figure 1,with the motor or engine removed.

Figure 3 is an enlarged fragmentary sectional and elevational View takenapproximately on the plane of the line 3-3 of Figure 2.

Figure 4 is a transverse vertical sectional view taken approximately onthe plane of the line 4 of Figure 3.

Figure 5 is an enlarged vertical sectional view taken on the plane ofthe line 5-5 of Figure 1.

Figure 6 is an elevational View of the triangular hanger or adapter forthe double acting or duplex grinding head.

Figure 7 is a section taken on the plane of the line l'i of Figure 2.

Figure 8 is a fragmentary detail section taken approximately on theplane of the line 8-8 of Figure 6.

Figures 9 and 10 are detail elevational views of the companion disk-likesections of the circular grinding and surfacing head.

Figure 11 is a group assembly sectional and elevational view disclosingthe co-acting elements of said head sections.

Figures 12 and 13 are detail views of the toothed spur-wheels whichserve as the grinding elements in the wheel or disk assemblies.

Figure 14 is an elevational view of the triangular adapter plate orhanger per se.

Figure 15 is a side elevational view, like Figure 1, showing a differentembodiment of the invention hereinafter differentiated as the singlegrinder type.

Figure 16 is a top plan view of the tiltable platform or frame formingthe chassis of the two-wheeled truck.

Figure 17 is a fragmentary sectional and elevational view detailing thegear and shafting drive for the dust collector fan and grinding head,said figure being taken approximately on the plane of the line i1-l1 ofFigure 18.

Figure 18 is a transverse vertical sectional view taken at right anglesto Figure 17 on the line I8l8 of Figure 17.

Figure 19 is a section taken approximately on the plane of the irregularline I 9! S of Figure 15.

Figure 20 is a top plan view of the frontal portion of the machine,looking down on Figure 17, for example.

Figure 21 is a detail elevational view of the steering handle.

By way of introduction to the detailed description, it is to be pointedout that the accompanying drawings illustrate two distinct types orembodiments of the machine. The so-called duplex grinder type is shownprincipally in Figure 1 and its associated accessories and parts aredepicted in Figures 1 to 14 inclusive. Then in Figures 15 to 21,inclusive, is shown the single grinder type for the simplified style ofroad surfacing machine. For sake of clearness of description, thesefigures, that is, l to 14 on the one hand and 15 to 21 on the other,will be successively described in the order in which they occur. It willbe obvious, however, as the description proceeds, that the two forms ofthe invention possess many common or generic features of construction.Therefore, the language will be comprehensively used to compensate forthis slight variance.

Reference is to be had first to Figures 1 to 14, inclusive. Directingattention initially to Figures 1 and 2, the general assembly can beeasily discerned. Briefly, this comprises a two-wheeled truck with aprime mover or suitable power means on one end and on one side of theaxle, and a forwardly and upwardly extending beam carrying at its outerend the duplex grinding means, said grinding means being suspended orhung by compensating means and there being an appropriate drive betweenthe prime mover and grinding means. Specifically the truck is of simpletype and comprises a pair of duplicate wheels W mounted on the oppositeends of an axle A which supports the frame or chassis. The frame orchassis embodies a suitable platform 25 to support a conventionalgasoline engine or motor M. On the left hand side of the axle A andprojecting forwardly and upwardly is a suitably shaped obtrudingextension which may be conveniently described as a beam 26. The beamterminates in a box-like integral unit 2'! which is hereinafterspecifically referred to as suspension means. Bolted or otherwisesecured, as at 28, to this suspension means is the steering handleembodying a shaft 29 and hand-grip 3i). This arrangement expediteshandling and maneuvering of the machine for working and transportationpurposes. It will be noted that by placing the motor on one side of theaxle and the grinding means on the forward or other side, proper uniformbalance is established to promote expeditious handling of this otherwisecumbersome machine. Incidently, the drive shaft, which is horizontallydisposed, is differentiated by the numeral 3| and is coupled to themotor shaft S through the instrumentality of a conventionalautomatically operable speed controlled clutch C.

-I call attention now to Figure 3, wherein the configuration and form ofthe suspension means 21 is illustrated. Here it will be observed thatthe numeral 32 designates a drive shaft bearing which accommodates theleft hand end portion of the shaft 3! and which includes a cup 33 toaccommodate the ball race and an attaching flange 34 by means of whichit is bolted to the suspension means 21. The cup 33 protrudes into saidpart 21 and constitutes a support for the swingable dependingtransmission case 35. That is to say, the body portion 36 of this caseis rockably suspended from the shaft bearing or cup 33. The numeral 31designates a detachable cover plate. Incidently, while this transmissioncase may be designed to accommodate gearing in this particularembodiment of the invention, it is shown constructed to accommodate asprocket chain and wheel drive. Referring to Figure 5, it will be seenthat the drive shaft is provided with a sprocket wheel 38 over which thesprocket chain 39 is trained. The numeral 40 designates an idler whichis positioned to reverse the motion of the complemental sprocket wheels4| and 52 carried by the shafts 43 which constitute the driven shaftsand which serve to support and operate the duplex grinding heads 44 and45.

The shafts 43 are journaled in individual bearings 48 and 41 (see Figure14) integrated with the triangular hanger plate or adapter plate 48. Atits apex portion, the plate is provided with a bearing 49 mounted forlimited pendulus or swinging motion on a horizontal suspension pin 53carried by the bearing in the part 27, as shown in Figure 3. It is, ofcourse, obvious that the sprocket-equipped ends of the driven shafts 43extend through the cover plate 31 and into the transmission case so thatthe transmission case is coupled to the pendulus hanger 48, causingthese parts 48 and 35 to operate in unison. The parts togetherconstitute broadly compensating means, allowing the grinding heads 44and 45 to adjust themselves to the irregularities in the surface beingacted on.

Referring now to Figure 8 showing the detailed mounting of the grinderhead, it will be observed that this head, as a unit, bears at its innerend against a stop washer 52 backed against the shoulder 53 on the shaft43. The outer end spindle portion 54 is constructed to accommodate thehead and threaded to take care of a clamping nut 55 clamping theretaining washer 56 in place. This promotes expeditious and practicableapplication and removal of the head as a unit.

Each grinding head is the same in construction and a description of onewill suffice for both. To begin with, it will be observed that the head,as a unit, is of general circular form. Moreover, it is equipped withperipherally arranged cutting and grinding assemblies. Each assembly iscomposed of a gang of toothed or spur-wheels 51 of the type shown inFigures 12 and 13. These are transfixed on the periphery of the head totravel in an orbital path. Moreover, these spur-wheels are independentlyrotatable on their own axes. Thus we have a revoluble head havingperipheral grinding and cutting elements of a self-accommodating type inthat they have independent rotary action. Consequently, as the head israpidly whirled, it virtually spins the rotatable cutting wheel 5?against the surface being ground. Because of this flexibility of action,the grinding I head does not fracture or spall the ragged edges ofdepressions and elevated expansion joints, etc. It has been discernedthat with the marketed types of machines where the complete grindingsurface of the horizontally disposed disk is in contact with theconcrete, it causes chipping, crumbling and flaking, thus hampering theaccomplishment of the job in a satisfactory manner.

It is further to be noted in connection with these particular grindingheads that the gangs or assemblies of spur-wheels are located instaggered or alternating relationship on the periphery of the head. Thispermits them to serve their appointed share in the grinding action in anintermittent but continuous cutting operation. That is to say, itpromotes the proper rasping contact action essential in grading theconcrete down to a smooth and even finish.

In making up the heads, it has been found advisable to construct eachone from a pair of companion duplicate disk-like sections 58 and 59, as

shown in Figures 9 and 10. These sections are centrally bored andslipped over the spindle 54. They are provided with empaling pins 60which serve'to transfix the toothed spur-wheels 51 in the accommodationpockets 6| provided therefor. Each pocket has a socket 62 to accommodatethe free end of the pin. Hence by simply separating the two parts 58 and59, the toothed wheels can be slipped off of the pins and interchangedand replaced to promote satisfactory operation at all times. This isindeed a unique assembly and arrangement. It is, of course, evident thatthe pockets are of a depth to permit the toothed edge portions of thewheels to project beyond the peripheral surface of the grinding head.

Also, the pockets and pins are properly inter-related to provide for thestaggered disposition of the spur-wheels.

It has been observed that when the grinding heads are out of contactwith the work and idling, there is a tendency to develop an unusualstrain and torque on the shafting and features making up the sprocketdrive. To compensate for this, I have evolved and produced a uniquetorque equalizing means which is illustrated in Figure '7. This has a.tendency to stabilize and centralize the hanger 48 so that it occupies asubstantially normal depending position. The preferred embodiment of themeans comprises a coiled spring 63 bearing against the hanger andsupported in a nut 84 threaded into one of the side flanges of thechannel-shaped suspension means 21. The numeral 85 is merely a stop boltalso threaded to the nut and into the sprmg, and 66 is a lock nut. Thisis a highly necessary accessory in a machine of this type since withoutit the two shafts 3| and 43 are subjected to unusual wear and tear.

Some of the structural features to be emphasized in conjunction with theembodiment of the GO invention just concluded are these. First, I desireto emphasize the idea of utilizing the doubleacting, oppositely rotatinggrinding heads spaced apart and supported on pendulus compensating meanswhereby to permit them to be substantially c5 self-leveling to conformto irregularities in contour and to better perform their assigmnents.Incidently, if it is desired, a suitable guard 61 may be provided toaccommodate these grinding heads. T0

rotate on horizontal axes at right angles to the truck axle and disposethe cutting peripheral surfaces in position to contact the surface beingacted on. The intermittent grinding and cutting action is important. Theequi-distant spacing of the grinding and cutting spur-wheels isimportant. The independent rotation of the spurwheels themselves on therevoluble head is distinct and an unusual refinement.

The co-ordination of the hanger 48 with the transmission casing 35 is apracticable achievement. Moreover, the adaptation of the specialbox-like unit 2'! to accommodate these interrelated parts 35 and 48 isunique.

Then too, the resilient pressure action of the torque equalizing deviceshown in Figure '7 to normalize the position of the part 48 is aninnovation in a machine of this type. The uniform and well balancedarrangement of all the parts of the machine in relation to the motor andtruck is practicable and eflicient and the handle 29 on the forwardportion thereof permits the machine to be transported and properlymaneuvered.

The integrated formation of the entire frame tiltably mounted on thetruck wheels and carrying the prime mover at one end and the grindingand power transmission means at the other end is well suited for theintended purposes. It is to be noted that the part 21, which serves asthe suspension means for the transmission casing and adapter, is ofhood-like construction. Thus made, it is aptly fitted for the purposesintended. In fact, it is thought that the parts as mutually connected,transcend in importance and performance similar parts found in prior artconstructions.

Coming now to the single grinder type of the invention illustrated inFigures 15 to 21, attention is directed to Figure 16. Here the numeral61 designates the chassis or frame having a platform 68 at its rear endto accommodate the gasoline engine or motor M. The automatic clutch isindicated at C in Figure 15 and the drive shaft is indicated at 69. Thisis housed in a shield '50 attached to the frontal plate or base portion'll of the frame. The frame is fulcrumed to rock on a transverse axis,that is on the axle A supported by the wheels W. The frontal portion ofthe base is bifurcated and the furcations are denoted by the numeral 12.It is between these parts that the principal features of the inventionare supported. The latter assembly of parts is shown better in Figure17. Here the gear casing is indicated by the numeral 13 and provided atits front with an attaching flange M bolted or otherwise secured to thefurcations 12. The gear casing is formed at its bottom with an extensiondefining a bearing 15 for the driven shaft 16 which operates the singlegrinding head Il. Incidently, this head is of the same construction asthe heads already described and corresponding numerals are employed todesignate like parts. At its upper portion, the gear casing is providedwith a bearing 18 to accommodate the adjacent end portion of the driveshaft 69. This shaft is provided with a gear 19 meshing with an idlergear 83 which in turn drives a power take-off gear Bl on the drivenshaft 16. Thus the motion is transmitted from the shaft 69 to the shaft16 to operate the head H,

In this arrangement, I utilize a dust collector system and guard for thegrinding head. The dust collector means comprises a fan housing 82 toaccommodate the suction fan 83 carried by the left hand end of the shaft69. The shaft 69 projects through the gearing housing or casing into thefan casing. The fan casing is secured by spacing studs 84 and 85 andboth to the attaching flange 14. The cover plate 86 is provided with adust intake 81 embodying a communicating dust intake nozzle 88, as shownin Figure 19. This same casting which forms the nozzle and cover 5 plateis fashioned to provide a segmental guard 89 for the grinding head. Thedust discharge or outlet is shown at 90 in Figure 20.

The operating handle is indicated at 9| and is provided with a yoke 92attachable to the frame 10 for raising and lowering it for appropriategrinding and releasing action.

In the duplex arrangement, that is, the opposed oppositely operatinggrinding heads (Figures 1 to 14:, inclusive) the heads stick to the sur-15 face in a self-accommodating manner. It has been observed, however,that with the single head arrangement, the operator can concentrate morereadily on the high place on the road surface despite the additionaleifort and energy required. 20 It is also evident that in the doubletype, the arrangement is slightly more complex, whereas in the singlearrangement, simplification and econonw prevail.

In comprehending the following claims, it is 25 desired that the termtruck be interpreted to comprehend any sort of a transportable vehicleor conveyance which is adapted to support the motor and grinding meansand to facilitate its movement to and from the job, as well as itsexpedi- 30 tious handling and maneuvering in the vicinity of the work.In both forms of the machine it will be observed that the drive anddriven shafts are in vertically superposed parallelism in order totransmit the power from an elevated point to a 35 point within thevicinity of the surface and to accomplish this either through directgearing or a sprocket chain drive, as is desired. In both forms of theinvention, the motor or prime mover is supported on one side of the axleand the entire weighted grinding means on the other side of the axle ata point remote and in advance of the axle, at which point the steeringand maneuvering handle is attached. It will be observed in fact thatthere are many generic and common features r existing between the twostyles of machine. For example, it will be noted that in both forms ofthe invention the remote power means or prime mover drives one or morecircular grinding heads, with the heads rotatable around the horizontalaxes, that is, attached to a horizontal shaft and with the equi-distantor alternating, intermittently operating free rotating toothed disk onthe peripheral portion of the head. Here is a continuity andco-ordination of features which, it is believed, will satisfy therequirements of the trade.

From the foregoing it will be seen that novelty is predicted on theadoption and use of a lowbuilt portable gasoline engine-driven machine60 of a perfectly balanced type such as may be justly endorsed by thetrade for concrete road surfacing and servicing work. As constructed inaccordance with the invention, the machine is perfectly proportioned andeasily controlled permit- 65 ting the work to be done with utmostaccuracy. The machine is of a self-contained power type whereinsufficient power is furnished by a simple economical power plant tooperate the rotary grinding tool as well as the dust-collecting system,permitting the dust to be rapidly removed as it accumulates so that thecutting head is always working on a clean surface. This not onlyincreases the efficiency of the machine but 75 enables the operator tosee exactly what he is doing.

Due to the proper counterbalancing construction of the frame and itsappurtenances, it is evident that the grinder cuts the concrete surfacewith a smooth even action and produces no jumping or chattering. In asense, it involves a new principle in construction in that it embodies ahigh-speed grinding tool embodying self-accommodating cutters which dotheir work at a rapid rate, this being accomplished by placing thecutters around the outer rim or periphery of the drum-type cutter head.The rotary action of the cutter head placed on a horizontal axis, givesa smooth keen cutting action. Although, it is of secondary importance,the particular construction of the cutter head, that is, a structuremade in sectional parts to provide for renewal of the toothed cuttingdisks, is an added improvement.

Of superior importance tothe sensitive counterbalancing idea is thespecial conception which involves the special adaptation and use of astructural assemblage which invokes the unique idea of utilizing thesimple two-wheeled truck as a compensating and mobile support in orderto provide the requisite or transverse or horizontal axis on which theframe may be rocked as well as the upright axis around which the framemay be swung in a substantially horizontal plane parallel to the surfacewhile being moved up and down to take care of varying contingencies; inconjunction with an appropriate grinding head having road grinding meanson its periphery and suitable means, preferably a tool shaft, to serveto rotate the head on the frame so that the axis of the head extends ina direction substantially at right angles to the transverse axis and ina plane substantially parallel to the surface being worked to allow theperipheral grinding means to properly contact and adjustably engage saidsurface.

It is believed, however, that persons skilled in the art to which theinvention relates will be able to appreciate the features andadvantages, the weight and stress distribution, and the specialmaneuvering activity of the handle, for which reason a more lengthydescription is deemed unnecessary.

I claim:

1. A grinding and abrading head for use in association with a roadsurfacing machine of the class described comprising a shaft adapted forhorizontal rotation, said shaft including a spindle, a grinding headmounted on said spindle, said head embodying a pair of substantiallyduplicate disk-like sections arranged in abutting contact, the opposedfaces of said sections being provided with alternating cavities formingdisk receiving pockets, the portions of the sections between saidcavities being provided with empaling pins to span the pockets, eachpocket being provided with a counter-bore forming a socket for receptionof the free end portion of the adjacent or complemental pin, and a groupof toothed cutting wheels mounted for rotation on each pin and locatedin a complemental pocket.

2. A road surfacing machine of the class described comprising a truckincluding a wheelsupported axle, a frame mounted on said axle, a primemover attached to one end of the frame and located rearwardly of theaxle, a horizontally disposed drive shaft supported on the frame andoperatively connected with said prime mover, a

horizontally disposed bearing associated with the front end portion ofsaid frame and adapted for disposition in close proximity to the surfacebeing treated, a driven shaft mounted for rotation in said bearing, saidshafts being disposed in superposed parallelism, means operativelyconnecting the two shafts together, a steering and maneuvering handleattached to the frontal portion of said frame, and a grinding headattached to the horizontal driven shaft.

3. A machine of the class described comprising a power-equippedwheel-supported frame including a forwardly extending power actuateddrive shaft, a power transmission casing mounted on the forward endportion of said frame and depending into close proximity to the work,said casing being provided at its lower end with a horizontal bearing,said drive shaft extending through the upper end portion of the casing,a gear connected with said drive shaft, a driven shaft mounted forrotation in said bearing, an operating connection between said drivenshaft and said drive shaft for simultaneously operating the shafts, anda grinding head on the front end of said driven shaft.

4. A machine of the class described comprising a motor-equippedwheel-supported frame including a forwardly extending motor actuateddrive shaft, a gear casing mounted on the forward end portion of saidframe and depending into close proximity to the work, said gear casingbeing provided at its lower end with a horizontal bearing, said driveshaft extending through the upper end portion of the gear casing, a gearconnected with said drive shaft, a driven shaft mounted for rotation insaid bearing, gearing connecting said driven shaft with said drive shaftfor operating the shafts, a grinding head on said driven shaft, a dustfan casing attached to said gear casing, a fan located in said fancasing, said drive shaft extending into the fan casing and attached tosaid fan, said fan casing including a cover having a guard partiallysurrounding the peripheral portion of said head and further including adust intake nozzle for delivering dust and dirt into the fan casing,said fan casing being provided with an outlet.

5. A machine of the class described comprising a truck including atiltable frame having a motor supporting platform and a forwardlyextending beam, said beam terminating at its forward end in a suspensionunit, said unit include ing aligned bearings, a drive shaft having oneend portion supported in one of said bearings, a hanger pin supported inthe remaining bearings, a transmission casing swingably mounted on oneof said bearings and depending from said suspension unit, an adaptationhanger swingably supported from said hanger pin and including ahorizontal bearing, a driven shaft mounted in said horizontal bearing, agrinding head attached to one end of said driven shaft,and an operatingconnection between said shafts, said means being located in saidtransmission casing.

6. A machine of the class described comprising a portable supportincluding a frame, a swingably mounted hanger on said frame including apair of horizontal spaced parallel bearings, driven shafts mounted forrotation in said bearings, operating means for said shafts, and grindingheads on the forward ends of said shafts.

'7. A machine of the class described comprising a portable supportincluding a frame, a swingably mounted hanger on said frame including apair of horizontal spaced parallel bearings, driven shafts mounted forrotation in said bearings, operating means for said shafts, and grindingheads on said shafts, and means for turning said heads in directionsreverse to each other so as to cause the heads to remain inself-accommodating contact with the surface being treated.

8. A surfacing machine of the class described comprising a portabletruck including a frame having a beam formed at its forward end with aninverted hood-like suspension unit, a vertically elongated dependingtransmission housing hung for swingable movement in said suspensionunit, a drive shaft extending into said casing and provided with adriving element, a pendulous hanger mounted for swinging movement insaid suspension unit and provided with bearings, driven shafts mountedfor rotation in said bearings and having their rear ends extending intosaid transmission housing and provided with driven elements, an idleralso in said housing, a power transmission chain engageable with all ofsaid elements in a manner to turn said shafts in reverse directions, andgrinding heads on said driven shafts.

9. A surfacing machine of the class described comprising a portabletruck including a frame having a beam formed at its forward end with aninverted hood-like suspension unit, a vertically elongated dependingtransmission casing hung for swingable movement in said suspension unit,a drive shaft extending into said casing and provided with a sprocketwheel, a pendulous hanger mounted for swinging movement in saidsuspension unit and provided with horizontal bearings, horizontal drivenshafts mounted for rotation in said bearings and having their rear endsextending into said transmission casing and provided with sprockets, anidler sprocket also in said casing, a sprocket chain engageable with allof said sprockets in a manner to turn said shafts in reverse directions,and grinding heads on the forward ends of said shafts, together withresilient torque equalizing means on said suspension unit co-operablewith said pendulous hanger.

10. A low-built concrete road surfacing and grinding machine of aone-man portable type comprising a relatively low transporting andmaneuvering truck provided with independent idling wheels, a low-slunghorizontally elongated chassis frame fixedly fulcrumed intermediate itsends on said truck, a prime mover on one end of the frame, a grindingtool and operating means therefor on the opposite end of the frame, saidtool and associated means possessing an aggregate weight substantiallyequivalent to that of the prime mover in order to uniformly balance theframe on said truck, said grinding tool being of a rotary circular drumtype revolvable about a horizontal axis disposed at right angles to saidtruck and embodying marginal grinding means, whereby to permit said toolto roll and ride from side to side while in contact with the surface andto swing in an arcuate path with respect to the truck during which timethe truck wheels compensate for such swinging movements, and a handlestructure associated with the toolequipped end of said frame, andincluding an upstanding reach rod attached to the frame at its lower endand provided at its upper end with handle bars, said handle bars beinglocated beyond the tool and sufficiently elevated to permit the tool tobe controlled either by a downward thrust action and/or lateral swingingmovement in a horizontal plane.

11. A portable concrete road surfacing and grinding machine of the classdescribed comprising a truck including a horizontal axle, a pair ofwheels mounted for free rotation on said axle, a frame fixedly fulcrumedintermediate its ends on said axle, a source of power mounted on theframe and located rearwardly of the axle, surface grinding meansattached to the forward end of the frame and balanced in relation to thesource of power and supporting rear end of the frame, an automatic speedcontrolled clutch 10 equipped operating connection between the source ofpower and said grinding means for operating the grinding means only whenit is in working contact in the surface being worked, a steering andmaneuvering handle attached to 15 the forward end of the frame above andextending outwardly beyond said grindin means, said grinding meansembodying a rotary tool operable on an axis substantially at rightangles to said shaft, and said tool further including self adaptingperipheral grinding elements.

12. As a component part of a road surfacing machine of the classdescribed, a grinding and abrading head comprising a supporting androtating shaft, said head embodying a pair of duplicate companionsections having their inner or adjacent faces in direct abuttingcontact, the opposed faces of said sections being provided with aplurality of cavities forming marginal pockets, the outer open ends ofsaid pockets opening through the peripheral or marginal rim of the head,retaining and pivot forming pins mounted in said pockets, and toothedcutters fitted into said pockets, said cutters being retained in placeby said pins, being rotatably mounted on the pins, and the cutting teeththereon projecting through the outer open ends of the pockets and beyondthe rim of the head.

13. In a road surfacing machine, and in combination, a mobile supportingstructure for movement on a road surface being worked, a frame on themobile structure, said mobile structure including means whereby theframe may be rocked on a transverse axis substantially parallel to saidsurface being worked and simultaneously and/or independently swung on anupright axis, a cylindrical head having road grinding means about 'itsperiphery, means rotatably mounting the head on the frame so that theaxis of the head extends in a direction substantially at right angles tosaid transverse axis and in a plane substantially parallel to saidsurface being worked and so that the grinding means on the head mayengage the surface being worked, a prime mover on the frame operativelyconnected to the head for rotation thereof, and handle means on theframe, whereby an operator may maneuver the machine to rock the same onsaid transverse axis for engaging and disengaging the head with respectto the surface being worked and when the head is engaged with saidsurface, the operator may swing the frame on said upright axis causingthe head to move from side to side in an arc concentric with respect tosaid upright axis.

14. In a road surfacing machine, and in combination, a mobile supportingstructure for movement on a road surface being worked, a frame having anintermediate portion thereof mounted on the mobile structure, saidmobile structure including means whereby the frame may be rocked on atransverse axis substantially parallel to said surface and may be swungon an upright axis, a cylindrical head having road grinding means aboutits periphery, means rotatably mounting the head on the frame so thatthe axis of the head extends in a direction substantially at rightangles to said transverse axis and in a plane substantially parallel tosaid surface being worked and so that the grinding means on the head mayengage the surface being worked, said cylindrical head being locatedadjacent one end of the frame, a prime mover on the other end of theframe operatively connected to the head for rotation thereof and beingof such a weight as to partially counter-balance the head, and handlemeans on the end of the frame adjacent the head, whereby an operator mayadjust and regulate the machine to rock the same on said transverse axisfor engaging and disengaging the head with respect to the surface beingworked and when the head is engaged with said surface the operator mayswing the frame on said upright axis causing the head to move from sideto side in an arc concentric with respect to said upright axis.

15. A low-built concrete road surfacing and grinding machine of theportable one-man type comprising a relatively low transporting andmaneuvering truck including a horizontal axle having idling wheels atits ends, a low slung chassis rockably mounted on said axle, a source ofpower on one end of the chassis, irregular concrete surface grinding andlevelling means on the opposite end of said chassis, the ratio of weightof the opposite ends of the chassis including the source of power andsaid grinding means being such that the chassis is uniformlycounterbalanced on said axle to allow the grinding means to be easilyadjusted toward and from the surface, a handle structure attached to theend of the chassis adjacent said grinding means and elevated above saidmeans and located in respect thereto to permit the chassis to behorizontally swung from side to side in an arcuate path, said grindingmeans embodying a horizontally disposed tool shaft located at rightangles to the aforementioned axle and including a tool on said shaft,said tool being mounted for rotation about the horizontal axis of saidshaft.

16. In a structural assemblage of the class described, a. portablepower-equipped support including a drive shaft and a tool shaft, saidtool shaft being disposed in a horizontal plane and occupying a positionin alignment with the longitudinal dimension of the support, a grindinghead mounted on said tool shaft for rotation on a horizontal axis, saidgrinding head being of a circular type and including peripheral grindingmeans revolvable in an orbital path whose radius is at right angles tothe surface being treated.

17. A machine of the class described comprising a portable poweredsupport having manually controllable guiding and maneuvering handlemeans, and self adapting and levelling grinding means on said supportincluding a hanger freely swingable in a pendulous manner and disposedat right angles to the surface being treated.

18. In a structural assemblage of the class described, a portable powerequipped support having maneuvering and guiding handle means, aswingably mounted hanger on said support occupying a position at rightangles to the surface being treated, and a pair of closely spacedgrinding heads on said hanger for contact with the surface, said headsbeing mounted for turning on horizontal axes, being turnable indirections opposite to each other, and the grinding surfaces thereoftravelling in circular paths at right angles to the surface beingtreated.

19. As a component part of a structural assemblage of'the classdescribed, a substantially triangular hanger unit having supportingmeans at its top, and a pair of spaced parallel bearings at its bottom,tool shafts mounted in said bearings and disposed in spaced parallelhorizontal positions in relation to the surface being treated, andindividual drum-type grinder heads on the operating ends of said toolshafts, said grinder heads being provided with peripheral freelyrotatable grinding elements destined to revolve in orbital paths aroundtheir horizontal axes.

20. In a road surfacing machine, and in combination, a mobile supportingstructure for movement on a road surface being worked, a frame on themobile structure, said mobile structure including means whereby theframe may be rocked on a transverse axis substantially parallel to saidsurface being worked and may be swung on an upright axis, a pair ofcompanion simultaneously operable oppositely working cylindrical headshaving peripheral grinding means, means rotatably mounting the heads onthe frame so that the axes of said heads extendin directionssubstantially at right angles to said transverse axis and in planessubstantially parallel to said surface being worked, a prime mover onthe frame operatively connected with the heads for rotating said heads,and-handle means attached to the frame to facilitate maneuvering theframe and controlling the action of said heads.

21. In a machine of the class described, a portable. elongated frame, amotor carried by said frame and having a drive shaft extendinglongitudinally in relation to the longitudinal dimension of said frame,a driven shaft journaled for rotation in bearing means on the framebelow and substantially parallel to said drive shaft, an operatingconnection between said shafts, a surfacing tool operated by said drivenshaft and having its axis positioned normally lengthwise" of the frame,a fan housing associated with said driven shaft and having an inletconduit adjacent said tool to receive the grindings therefrom, and asuction fan mounted in said housing having operating connection with oneof said shafts.

22. A machine of the class described comprising an elongated frame, arolling support for said frame permitting vertical rocking movement ofthe frame, power means mounted on the frame, a main drive shaftrotatably mounted in said frame lengthwise with respect to thelongitudinal dimension of the frame and driven by said power means, atransmission housing receiving one end of said shaft and having abearing downwardly offset with its axis substantially parallel to saidshaft, a second shaft mounted in said bearing and having a surfacingtool thereon, power transmission means connecting said shaftsoperatively within said housing, a fan housing carried by the frame anddisposed over said bearing and in advance of said transmission housinghaving an inlet conduit partially embracing and shielding said tool,said fan housing being furthere provided with an outlet, and a fanmounted in said fan housing and driven by said first named shaft.

23. In a structural assemblage of the class described, a portablesupport, a frame mounted on said support, said frame being provided atits outer end with a power transmission housing assuming a verticallydisposed position, said transmission housing being provided at its lowerend with a horizontal bearing, a driven tool shaft mounted for rotationin said bearing, a tool carried by said shaft, one end of the tool shaftextending into said transmission housing, power supply means on saidframe, a power actuated drive shaft mounted for rotation on the frameand operatively connected with the power supply means and extendingthrough said transmission housing, an operating connection between saidshafts confined in said housing, a dirt and dust collector fan housingconnected with said transmission housing, said drive shaft extendinginto said fan housing and being provided with a fan, said fan housinghaving a marginal outlet and an intake nozzle, said intake nozzledepending therefrom and being fashioned to partially embrace said tool.

24. A road grinding machine of the class described comprising a manuallycontrollable portable support having power supply means, a rotary tooloperated by said power supply means and having surface grinding meansaround its periphery, said tool being rotatable on an axis substantiallyparallel to the surface being treated, and means operatively mountingthe tool on said support in a manner to permit the grinding means tohave self levelling contact with the surface and to be moved voluntarilytoward and from the surface while being swung back and forth in ahorizontal plane in a substantially arcuate path .and on a verticalaxis.

25. A portable road grinding machine of the class described comprising amobile frame, a rotary tool provided with grinding means on its marginalrim, and means for mounting the tool on said frame including ahorizontally disposed tool shaft movable vertically toward and from thesurface on a horizontal axis, and swingable on a vertical axis in ahorizontal plane while travelling in a substantially arcuate path inrelation to said vertical axis, said tool shaft being disposed, when inan inactive condition, at substantial right angles to said horizontaland vertical axes.

26. A portable road grinding machine comprising a power equipped mobilesupport'for manually controllable movement on the road surface beingconditioned, substantially horizontally disposed operating meansconnected with the source of power, a planetary rim-type grinding andsurface conditioning tool operatively connected with said horizontaloperating means and rotatable on an axis substantially parallel to saidsurface, and additional two-way pivotal means under the control of theWalking attendant permitting the tool to be swung laterally in anarcuate path on a vertical axis and to adjust itself vertically on ahorizontal axis, whereby to conform to the irregular contour beingtraversed or to be bodily lifted vertically for guiding andtransportation purposes.

HARRY L. MYERS.

